Welded knot end effector

ABSTRACT

An apparatus for forming an end effector includes a welding device having a welder positioned adjacent to a base, and a die coupled to one end of the welder. The base and the welder are movable relative to each other. The welder, base or die includes a source of heat that is applied to a portion of the suture disposed between the welder and the base.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of and priority to U.S.Provisional Patent Application Ser. No. 61/247,702, filed Oct. 1, 2009,the disclosure of which is herein incorporated by reference in itsentirety.

BACKGROUND

1. Technical Field

The present disclosure relates to sutures for use in medical procedures.More particularly, the present disclosure relates to a welded knot endeffector.

2. Background of Related Art

Medical sutures may be formed from a variety of materials and may beconfigured for use in limitless applications. The proximal end of thesuture may have a sharpened tip, or may include a needle, forpenetrating tissue. A distal end of the suture may include an anchor orend effector for maintaining the suture in engagement with the tissue asthe suture is pulled through the tissue. End effectors are available inmany size and configurations.

In many instances, a clinician may prefer to tie a knot in the suture toanchor the suture within the tissue. Although the clinician may findthis practice convenient, the knot formed on the end of the tissue isnot always suitable to prevent the suture from being pulled through thetissue, for example, the knot slips or is too small to engage thetissue. Additionally, the tying of a knot, especially with the finesuture material required for use in many procedures, is tedious and timeconsuming.

Therefore, a continuing need exists for an end effector and a method ofmaking an end effector.

SUMMARY

A method of forming a welded end effector is presently disclosed. Themethod includes providing a length of suture including a knot and awelding device selectively engagable with the knot, the welding deviceincludes a base and a welder. Additionally the method includespositioning a portion of the suture within a welding device, activatingthe welding device and reducing the gap between the welder and the baseto weld the knot. Activating the welding device may include activatingcontact heating, radiant heating or ultrasonic welding. The gap betweenthe welding device and the base may be from 0.001 inches to 0.05 inches.The knot may include a first section and a second section, each of thefirst and second sections including a plurality of throws.

Also disclosed is a welding device for forming a welded end effector.The welding device includes a base and a welder positioned adjacent tothe base. The welder may include a die extending towards the base. Thewelder is capable of relative movement with respect to the base. The diemay be made of titanium. The base may include grooves to form a raisedportion on the welded end effector to enhance engagement of the weldedend effector with a tissue. The welding device is configured to retain adistal end of a suture between the die and the base.

Further disclosed is a system for forming an end effector. The systemincludes a suture and a welding device. The suture may include a bodyportion defining a longitudinal axis and a knot integrally formed fromthe body portion. The welding device may include a welding device havinga die coupled to one end of the welder and a base supporting at least aportion of the suture and a welder positioned adjacent to the base andmovable relative to the base. Relative movement of the welder and thebase compresses the knot disposed therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiment(s) given below, serve toexplain the principles of the disclosure, wherein:

FIG. 1 is a side view of an end effector according to an embodiment ofthe present disclosure;

FIG. 2 is a top view of the end effector of FIG. 1;

FIG. 3 is a perspective view of the end effector of FIGS. 1 and 2 priorto being welded;

FIG. 4 is a end effector welding device according to an embodiment ofthe present disclosure;

FIG. 5 is the end effector welding device of FIG. 4, during the weldingof an end effector;

FIG. 6 is a top view of a base for the end effector welding device ofFIGS. 4 and 5;

FIG. 7 is a top view of an alternate base of the end effector weldingdevice of FIGS. 4 and 5;

FIG. 7A is a partial cross-sectional side view of the base of FIG. 7taken along lines 7A-7A of FIG. 7;

FIG. 8 is a bottom view of a forming die for the end effector weldingdevice of FIGS. 4 and 5;

FIG. 8A is a cross-sectional side view of the forming die of FIG. 8;

FIG. 9 is a bottom view of a forming die for the end effector weldingdevice of FIGS. 4 and 5;

FIG. 9A is a cross-sectional side view of the forming die of FIG. 9;

FIG. 10 is a bottom view of a forming die for the end effector weldingdevice of FIGS. 4 and 5;

FIG. 10A is a cross-sectional side view of the forming die of FIG. 10;

FIG. 11 is an alternate embodiment of an end effector according to thepresent disclosure, prior to being welded; and

FIG. 12 is a side view of an alternative embodiment of an end effectorafter welding according to the present disclosure.

DETAILED DESCRIPTION

Referring initially to FIGS. 1 and 2, an embodiment of an end effectoraccording to the present disclosure is shown generally as welded endeffector 10. Although, as shown, end effector 10 if formed on a firstend 12 a of suture 12, end effector 10 may be formed anywhere along thelength of suture 12. Suture 12 may be formed of degradable materials,non-degradable materials, and combinations thereof. More particularly,suture 12 may be formed of a degradable material selected from the groupconsisting of polyesters, polyorthoesters, polymer drugs,polydroxybutyrates, lactones, proteins, cat gut, collagens, carbonates,homopolymers thereof, copolymers thereof, and combinations thereof. Inother embodiments, suitable degradable materials which may be utilizedto form suture 12 include natural collagenous materials or syntheticresins including those derived from alkylene carbonates such astrimethylene carbonate, tetramethylene carbonate, and the like;caprolactone; dioxanone; glycolic acid; lactic acid; homopolymersthereof; copolymers thereof and combinations thereof. In someembodiments, glycolide and lactide based polyesters, especiallycopolymers of glycolide and lactide, may be utilized to form suture 12.

Suitable non-degradable materials which may be utilized to form suture12 include polyolefins, such as polyethylene and polypropylene;copolymers of polyethylene and polypropylene, and blends of polyethyleneand polypropylene; polyamides (such as nylon); polyamines; polyimines;polyesters such as polyethylene terephthalate; polytetrafluoroethylene;polyether-esters such as polybutester; polytetramethylene ether glycol;1,4-butanediol; polyurethanes; and combinations thereof. Other suitablenon-degradable materials include silk, cotton, linen, carbon fibers, andthe like. The polypropylene may be isotactic polypropylene or a mixtureof isotactic and syndiotactic or atactic polypropylene.

Suture 12 may be formed using any technique within the purview of thoseskilled in the art, such as, for example, extrusion, molding and/orsolvent casting. In some embodiments, suture 12 may include a yarn madeof more than one filament, which may contain multiple filaments of thesame or different materials. Where suture 12 is made of multiplefilaments, suture 12 may be made using any known technique such as, forexample, braiding, weaving or knitting. Suture 12 may also be combinedto produce a non-woven suture. Suture 12 may be drawn, oriented,crinkled, twisted, comingled or air entangled to form yarns as part ofthe suture forming process. In one embodiment, a multifilament suturemay be produced by braiding. The braiding may be done by any methodwithin the purview of those skilled in the art.

With reference still to FIGS. 1 and 2, welded end effector 10 isconfigured to prevent complete reception of suture 12 through tissue orother material. End effector 10 forms a flattened, substantiallydisk-shaped member 14 on a first portion 12 a of suture 12. End effector10 defines a horizontal axis “y” formed perpendicular to a longitudinalaxis “x” of suture 12. As will be discussed in greater detail below,configuration of the disk 14 depends on the size and configuration ofend effector 10 prior to welding and on the pressure applied by thewelding device 150 shown in FIG. 4.

Turning now to FIG. 3, end effector 10 is shown in a pre-welded form.Pre-welded end effector 10 a forms a knot several times thicker thansuture 12 on distal portion 12 a of suture 12. Pre-welded end effector10 a includes first and second sections 20, 30. Each of first and secondsections 20, 30 is formed form a plurality of throws 22 a-c, 32 a-c,respectively. As used herein, a throw is defined as an at leastthree-hundred and sixty degree (360°) wrapping or weaving of two limbs.As shown, first and second sections 20, 30 each include three throws 22a-c, 32 a-c. It is envisioned, however, that first and second sections20, 30 may include any number of throws 22, 32. It is further envisionedthat the number of throws on first section 20 need not be equal to thenumber of throws on second section 30. A second end 12 b of suture 12may include one or more needles (not shown). Suture 12 may include oneor more barbs along the length thereof.

For a more detailed discussion of pre-welded end effector 10 a,including methods of making the same, please refer to commonly ownedU.S. patent application Ser. No. 12/852,672, filed concurrentlyherewith, the content of which is incorporated herein by reference inits entirety.

Turning now to FIGS. 4 and 5, an apparatus for forming welded endeffector 10 is shown generally as welding device 150. Although discussedwith reference to welding end effector 10, welding device 150 may bemodified to weld end effectors of various shapes and sizes. Weldingdevice 150 includes a base or nest 160 for maintaining suture 12 duringthe forming of end effector 10 and a welder 170 for forming end effector10. Although throughout the remainder of the discussion reference willbe made to welder 170 as being of the ultrasonic variety, it isenvisioned that welder 170 may include any device capable of causingpre-formed end effector 10 a to become formable (i.e., other energysources, heat, light, etc.). It is also envisioned that the source ofheat or energy may be in the base 160 or the welder 170, or both.

With continued reference to FIGS. 4 and 5, base 160 of welding apparatus150 includes a substantially flat working surface 162 and an opening 164extending therethrough. Opening 164 may include a slot 164 a, as shownin FIG. 6, or may instead including a throughbore 164 b, as shown inFIG. 7. Opening 164 is configured to receive a second end 12 b of suture12 therethrough. The size of opening 164 may be varied depending on thesize of suture 12. In one embodiment, opening 164 is no greater thantwo-thousandths of an inch (0.002″) larger than the diameter of suture12.

Still referring to FIGS. 4 and 5, welder 170 includes a die 172 forforming end effector 10. Welder 170 may include a device capable ofultrasonically vibrating die 172. For example, welder 170 may include aBranson 20 KHz ultrasonic welder. Die 172 may be formed of titanium orother suitable material. Die 172 includes a contact surface 174 forengaging end effector 10 a. Contact surface 174 may be substantiallyflat, or instead contact surface 174 may include recess 174 a (FIGS. 8Aand 9A) and/or raised portion 174 b (FIG. 10A). Recess(es) 174 a may berectangular (FIG. 8), circular, oval (FIG. 9) or any otherconfiguration. Recess(es) 174 a are configured to form a raised orcontoured portion(s) (not shown) in a top surface of end effector 10during the welding process. Raised surface(s) 174 b is configured toform a recess(es) (not shown) in the top surface of end effector 10. Theraised surface(s) and/or recess(es) (not shown) formed in the topsurface of end effector 10 may be configured to enhance tissueengagement of end effector 10 and/or to facilitate grasping of endeffector 10. Welder 170 may weld the end effector 10 by any meansdesigned to soften pre-welded end effector 10 a, for example by applyingcontact heating, radiant heating or ultrasonic. It is envisioned thatbase 160 of welding apparatus 150 may include an ultrasonic mechanism(not shown) for ultrasonically vibrating base 160 during the forming ofend effector 10. In particular, welder 170 includes a source of heat orenergy as known in the art. It is envisioned that the source of heat orenergy source may be located in the welder, the die, the base, orcombinations thereof. The heat source may be an ultrasonic heat source,a radiant heat source, or a contact heat source.

Turning to FIG. 7, in one embodiment, working surface 162 of base 160includes grooves or indents 165 formed about opening 164. During weldingof end effector 10, grooves 165 form raised portions (not shown) in abottom surface of end effector 10. Alternatively, working surface 162may include one or more raised surfaces (not shown) for forming one ormore recess in the bottom surface of end effector 10 during welding ofend effector 10. The ridges and/or recess may be configured to enhancetissue engagement of end effector 10 and/or to facilitate grasping ofend effector 10.

With reference again to FIGS. 4 and 5, the operation of welding device150 will be described. Initially, a pre-welded end effector 10 a isformed in first end 12 a of suture 12 and any excess material is trimmedaway. Pre-welded end effector 10 a may be formed on site or instead beprovided on suture 12. Second end 12 b of suture 12 is then receivedthrough opening 164 of base 160 such that pre-welded end effector 10 ais received on working surface 162 of base 160 adjacent to ultrasonicwelder 170.

When using an ultrasonic heating source, welder 170 is then activated tovibrate die 172. Die 172 is then brought into contact with pre-weldedend effector 10 a to form end effector 10. In one embodiment, welder 170is configured to be approximated towards base 160. In anotherembodiment, base 160 is configured to be approximated towards welder170. In yet another embodiment, both base 160 and welder 170 areconfigured to be approximated towards one another. Regardless of whetherbase 160 and/or welder 170 is approximated, approximation between base160 and welder 170 occurs until a gap “G” is formed between workingsurface 162 of base 160 and contact surface 174 of die 172. The distanceof gap “G” is dependent on the thickness of suture 12, the size ofpre-welded end effector 10 a and/or the desired diameter of resultingend effector 10. In one embodiment, gap “G” ranged from one-thousandthof an inch (0.001″) to five-hundredths of an inch (0.05″).

Still referring to FIGS. 4 and 5, when using an ultrasonic energy sourcecontacting pre-welded end effector 10 a with contact surface ofvibrating die 172 causes pre-welded end effector 10 a to soften or melt.In one embodiment, the welding parameters range from half of a joule(0.5 J) to sixty joules (60 J) and includes a minimum hold time of aquarter of a second (0.25 s). Base 160 and/or welder 170 are moved awayfrom each other and suture 12 including end effector 10 is removed fromopening 164 formed in base 160. Welding of pre-welded end effector 10 aprevents unraveling of the end effector during use. Welding ofpre-welded end effector 10 a also increases the surface of end effector10 a that comes into contact with tissue forming disk 14 (FIG. 1),thereby distributing load force more effectively, allowing for a greaterload to be exerted before failure of either the tissue or end effector10.

With reference to FIG. 11, another embodiment of an end effector capableof use with welding device 150 prior to being welded is shown generallyas pre-welded end effector 210 a. Pre-welded end effector 210 a foil isa substantially T-shaped knot formed on first end 212 a of suture 212.Pre-welded end effector 210 a defines an axis “Y” extendingperpendicular to a longitudinal axis “X” of suture 212. Pre-welded endeffector 210 a includes first and second extensions 220, 230 extendingperpendicularly with respect to axis x from suture 212 in oppositedirections along axis “Y” to form a T-shape. Each of first and secondextension 220, 230 is formed from a plurality of throws 222 a-c, 232a-c, respectively, thereby forming undulated members. As shown, firstand second extensions 220, 230 each include three throws 222 a-c, 232a-c. It is envisioned, however, that first and second extensions 220,230 may include any number of throws 222, 232. It is further envisionedthat the number of throws on first extension 220 need not be equal tothe number of throws on second extension 230. A second end 212 b ofsuture 212 may include one or more needles (not shown) and/or mayinclude one or more barbs. Pre-welded end effector 210 a may be weldedin the same manner as described above with regards to pre-welded endeffector 10 a to form end effector 210 (FIG. 12).

Although the illustrative embodiments of the present disclosure havebeen described herein with reference to the accompanying drawings, it isto be understood that the disclosure is not limited to those preciseembodiments, and that various other changes and modifications may beeffected therein by one skilled in the art without departing from thescope or spirit of the disclosure.

1. An apparatus for forming a welded end effector, comprising: a weldingdevice having a welder positioned adjacent a base, at least one of thebase and the welder being movable relative to the other, wherein thebase defines an opening therethrough for reception of a suture; and adie coupled to one end of the welder, wherein relative movement of thewelder and the base compresses a knot located on a distal end of thesuture disposed therebetween, and wherein at least one of the welder,the base and the die includes a energy source.
 2. The apparatus of claim1, wherein the die is made of titanium.
 3. The apparatus of claim 1,wherein the suture knot is formed of a degradable material.
 4. Theapparatus of claim 1, wherein the suture knot is formed of anon-degradable material.
 5. The apparatus of claim 1, wherein the baseincludes grooves to form a raised portion on the welded end effector toenhance engagement of the welded end effector with a tissue.
 6. Theapparatus of claim 1, wherein the opening in the base defines a slot. 7.The apparatus of claim 6, wherein the slot extends from a lateral edgeof the base.
 8. The apparatus of claim 5, wherein the grooves areconcentric.
 9. The apparatus of claim 8, wherein the concentric groovesare formed about the opening in the base.
 10. An apparatus for formingan end effector, comprising: a welder; a base positioned adjacent thewelder, wherein at least one of the base and the welder is movablerelative to the other, wherein the base defines an opening for receiptof the suture body therethrough; and a die coupled to one end of thewelder, wherein at least one of the base and the die defines a pluralityof concentric grooves.
 11. The apparatus of claim 10, wherein relativemovement of the welder and the base compress a knot located on a distalend of a suture disposed between the welder and the base to form the endeffector.
 12. The system of claim 1, wherein the concentric grooves areformed about the opening in the base.
 13. The system of claim 12,wherein the opening in the base defines a slot.
 14. The apparatus ofclaim 13, wherein the slot extends from a lateral edge of the base. 15.The apparatus of claim 1, wherein the opening in the base defines alongitudinal axis extending through the die.
 16. The apparatus of claim1, wherein the opening in the base defines a longitudinal axis extendingalong a path of relative movement of the anvil and the base.
 17. Theapparatus of claim 10, wherein the base and the die each define aplurality of concentric grooves.